Allows us to define different watch versioning regimes in the future
as well as to encode information with the resource version.
This changes /watch/resources?resourceVersion=3 to start the watch at
4 instead of 3, which means clients can read a resource version and
then send it back to the server. Clients should no longer do math on
resource versions.
Move a lot of common error logging into better buckets:
glog.Errorf() - Always an error
glog.Warningf() - Something unexpected, but probably not an error
glog.V(0) - Generally useful for this to ALWAYS be visible
to an operator
* Programmer errors
* Logging extra info about a panic
* CLI argument handling
glog.V(1) - A reasonable default log level if you don't want
verbosity
* Information about config (listening on X, watching Y)
* Errors that repeat frequently that relate to conditions
that can be corrected (pod detected as unhealthy)
glog.V(2) - Useful steady state information about the service
* Logging HTTP requests and their exit code
* System state changing (killing pod)
* Controller state change events (starting pods)
* Scheduler log messages
glog.V(3) - Extended information about changes
* More info about system state changes
glog.V(4) - Debug level verbosity (for now)
* Logging in particularly thorny parts of code where
you may want to come back later and check it
Dawn Chen